People exist at different times. My life, for instance, consists of me-at-age-five, me-as-a-teenager, me-as-a-university-student, and of course many other temporal stages (or time-slices) as well. In a sense, then, we can see a single person, whose life extends over time, as akin to a group of people, each of whom exists for just a short stretch of time.
This perspective raises a host of interesting questions. Here’s one: Coherence is often considered a rational virtue. Rational people have beliefs, desires, and other attitudes that cohere with each, that fit together nicely, while having attitudes that clash with each other is a mark of irrationality. Certainly that’s the case for coherence at a single time. If there’s a time where you have inconsistent beliefs, then that’s irrational. But what about coherence over time? Is that a rational virtue too? Should your beliefs and desires held at different times fit together in any particular way? Should your actions, performed at. . .